Update visibility of libaudioserviceexampleimpl

In order for vendors to be able to use this library
it needs to have public visibility.

Bug: 205884982
Test: m
Change-Id: Idd47c942ee1e97372047ec1b44bcd996d454e3e2
diff --git a/audio/aidl/default/Android.bp b/audio/aidl/default/Android.bp
index 8bacbb3..c9edae0 100644
--- a/audio/aidl/default/Android.bp
+++ b/audio/aidl/default/Android.bp
@@ -92,9 +92,6 @@
         "audio_policy_configuration_aidl_default",
         "audio_policy_engine_configuration_aidl_default",
     ],
-    visibility: [
-        ":__subpackages__",
-    ],
 }
 
 cc_binary {